Encapsulation sheet, method of manufacturing organic light emitting display device using the same, and organic light emitting display device

ABSTRACT

In one aspect, an encapsulation sheet, a method of manufacturing an organic light emitting display device using the encapsulation sheet, and an organic light emitting display device is provided. The encapsulation sheet includes a carrier film; and a first sheet formed on the carrier film, wherein the first sheet comprises at least one of tin fluorophosphates glass, chalcogenide glass, tellurite glass, borate glass, and phosphate glass.

CROSS-REFERENCE TO RELATED APPLICATIONS

Any and all priority claims identified in the Application Data Sheet, orany correction thereto, are hereby incorporated by reference under 37CFR 1.57. For example, this application is a divisional of and claimspriority to U.S. application Ser. No. 13/779,410, filed Feb. 27, 2013which claims priority to and the benefit of Korean Patent ApplicationNo. 10-2012-0094443, filed in the Korean Intellectual Property Office onAug. 28, 2012, each of which is incorporated herein by reference in itsentirety.

BACKGROUND

1. Field

The present described technology generally relates to an encapsulationsheet, a method of manufacturing an organic light emitting displaydevice using the encapsulation sheet, and an organic light emittingdisplay device.

2. Description of the Related Technology

Organic light emitting display devices may have excellentcharacteristics in view of a viewing angle, a contrast, a responsespeed, and power consumption, and are expanding their application rangesto personal portable appliances such as MP3 players or mobile phones,and televisions (TVs).

Also, since organic light emitting display devices do not require anadditional light source due to a self-emissive characteristic thereof, athickness and a weight of the organic light emitting display devices maybe reduced.

However, the organic light emitting display devices may deteriorate dueto infiltration of moisture, and thus, it is very important to block theinfiltration of external moisture and oxygen into the organic lightemitting display devices.

SUMMARY

The present embodiments provide an encapsulation sheet having excellentmoisture and oxygen blocking property, a method of manufacturing anorganic light emitting display device using the encapsulation sheet, andan organic light emitting display device.

Some embodiments provide an encapsulation sheet including: a carrierfilm; and a first sheet formed on the carrier film, wherein the firstsheet includes at least one of tin fluorophosphates glass, chalcogenideglass, tellurite glass, borate glass, and phosphate glass.

In some embodiments, the encapsulation sheet may further include asecond sheet between the carrier film and the first sheet, wherein thesecond sheet includes tungsten.

In some embodiments, a encapsulation sheet may further include aplurality of additional first sheets and a plurality of additionalsecond sheets, where each first sheet is stacked alternately with eachsecond sheet. In some embodiments, at least one first sheet comprisestin fluorophosphates glass and the tin fluorophosphates glass comprisestin (Sn) by 20 to 80 weight %, phosphorus (P) by 2 to 20 weight %,oxygen (0) by 3 to 20 weight %, and fluorine (F) by 10 to 36 weight %.

In some embodiments, the encapsulation sheet may further include a thirdsheet between the carrier film and the first sheet, wherein the thirdsheet may be patterned as stripes, and the third sheet may includetungsten.

In some embodiments, the first sheet includes tin fluorophosphates glassand the tin fluorophosphates glass may include tin (Sn) by 20 to 80weight %, phosphorus (P) by 2 to 20 weight %, oxygen (O) by 3 to 20weight %, and fluorine (F) by 10 to 36 weight %. In some embodiments,the additional first sheet includes tin fluorophosphates glass and thetin fluorophosphates glass includes tin (Sn) by 20 to 80 weight %,phosphorus (P) by 2 to 20 weight %, oxygen (O) by 3 to 20 weight %, andfluorine (F) by 10 to 36 weight %.

Some embodiments provide a method of manufacturing an organic lightemitting display device, the method including: forming an organicelectroluminescence unit on a substrate; locating an encapsulation sheetthat includes a carrier film and a first sheet on the carrier film onthe organic electroluminescence unit; forming an encapsulation layerformed of the first sheet by heating the encapsulation sheet; andseparating the carrier film from the encapsulation layer, wherein thefirst sheet is formed of a low liquidus temperature material, and thelow liquidus temperature material may include at least one of tinfluorophosphates glass, chalcogenide glass, tellurite glass, borateglass, and phosphate glass. In some embodiments, the encapsulation sheetincludes tin fluorophosphates glass.

In some embodiments, the encapsulation sheet may further include asecond sheet formed between the carrier film and the first sheet.

In some embodiments, the method further comprises forming a plurality ofadditional first sheets and a plurality of additional second sheets,where each first sheet is alternately formed on each second sheet.

In some embodiments, the second sheet may include tungsten.

In some embodiments, the low liquidus temperature material and thetungsten may react with each other when the encapsulation sheet isheated to a temperature. In some embodiments, the temperature of theheat may be 200° C. or less. In some embodiments, the temperature of theheat may be from about 150° C. to 200° C.

In some embodiments, the encapsulation sheet may further include anintermediate layer between the carrier film and the first sheet.

In some embodiments, the first sheet includes tin fluorophosphates glassand the tin fluorophosphates glass may include tin (Sn) by 20 to 80weight %, phosphor (P) by 2 to 20 weight %, oxygen (0) by 3 to 20 weight%, and fluorine (F) by 10 to 36 weight %.

In some embodiments, a temperature of the heat applied to theencapsulation sheet may be 200° C. or less.

Some embodiments provide an organic light emitting display deviceincluding: a substrate; an organic electroluminescence unit; and anencapsulation layer sealing the organic electroluminescence unit,wherein the encapsulation layer is formed of a glass material, and theglass material includes at least one of tin fluorophosphates glass,chalcogenide glass, tellurite glass, borate glass, and phosphate glass.

In some embodiments, the encapsulation layer may further includetungsten, and the tungsten is included by 0.1 to 15 weight %.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present embodimentswill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a cross-sectional view of an organic light emitting displaydevice according to an aspect of the present embodiments;

FIG. 2 is an expanded view of a portion P in FIG. 1;

FIGS. 3 through 5 are perspective views of encapsulation sheets formingan encapsulation layer of FIG. 1; and

FIGS. 6 through 8 are cross-sectional views illustrating a method ofmanufacturing the organic light emitting display device of FIG. 1.

DETAILED DESCRIPTION

The present disclosure will now be described more fully hereinafter withreference to the accompanying drawings, in which illustrativeembodiments are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout.

It will be understood that although the terms first and second are usedherein to describe various elements, these elements should not belimited by these terms. These terms are only used to distinguish oneelement from another element. Thus, a first element discussed belowcould be termed a second element, and similarly, a second element may betermed a first element without departing from the teachings of thisdisclosure.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items. Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.

Hereinafter, embodiments of the present disclosure will be described indetail with reference to accompanying drawings.

FIG. 1 is a cross-sectional view of an organic light emitting displaydevice 10 according to an embodiment, and FIG. 2 is an expanded view ofa portion P shown in FIG. 1.

Referring to FIGS. 1 and 2, the organic light emitting display device 10according to an embodiment includes a substrate 101, an organicelectroluminescence unit 100 formed on the substrate 101, and anencapsulation layer 200 sealing the organic electroluminescence unit100.

In some embodiments, the substrate 101 may be formed of a glassmaterial, or may be formed of a plastic material such as acryl,polyimide, polycarbonate, polyester, or mylar in order to addflexibility to the organic light emitting display device 10. Also, aninsulating layer 102 such as a barrier layer and/or a buffer layer forpreventing impurity ions from dispersing, preventing infiltration ofmoisture or external air, and planarizing a surface may be formed on anupper surface of the substrate 101.

In some embodiments, the organic electroluminescence unit 100 mayinclude a driving thin film transistor (TFT) Ml and an organic lightemitting diode (OLED) formed on the substrate 101, as shown in FIG. 2.Meanwhile, FIG. 2 shows a front emission type organicelectroluminescence unit 100 as an example; however, the presentembodiments are not limited thereto, that is, the organicelectroluminescence unit 100 may have a rear emission type structure orother various structures that are different from the configuration ofFIG. 2.

In some embodiments, an active layer 107 of the driving TFT M1 may beformed of a semiconductor material, and a gate insulating layer 103 maybe located to cover the active layer 107. In some embodiments, theactive layer 107 may be formed of an inorganic semiconductor materialsuch as amorphous silicon or polysilicon, or an organic semiconductormaterial.

In some embodiments, a gate electrode 108 may be formed on the gateinsulating layer 103, and an interlayer dielectric 104 may be formed tocover the gate electrode 108. In some embodiments, source/drainelectrodes 109 may be formed on the interlayer dielectric 104, and apassivation layer 105 and a pixel defining layer 106 may be sequentiallyformed to cove the source/drain electrodes 109.

In some embodiments, the gate electrode 108 and the source/drainelectrodes 109 may be formed of metal such as Al, Mo, Au, Ag, Pt/Pd, orCu. In some embodiments, a resin paste including the above metal aspowder may be applied or a conductive polymer may be used to form thegate electrode 108 and the source/drain electrodes 109.

In some embodiments, the gate insulating layer 103, the interlayerdielectric 104, the passivation layer 105, and the pixel defining layer106 may be formed of an insulating substance to have a single-layered ormulti-layered structure, and may be formed of an organic material, aninorganic material, or a compound of the organic/inorganic materials.

In some embodiments, although not shown in FIG. 2, a switching TFT and astorage capacitor may be formed through the same processes as those ofthe driving TFT M1. However, the stacked structure of the driving TFT M1is not limited to the above structure, and TFTs having variousstructures may be used.

In some embodiments, the OLED emits red, green, and blue light accordingto a flow of an electric current to display predetermined imageinformation, and may include a pixel electrode 110 that may be connectedto one of the source/drain electrodes 109 of the driving TFT M1, anopposite electrode 112 formed to cover entire pixels, and an organicemission layer 111 disposed between the pixel electrode 110 and theopposite electrode 112 to emit light.

In some embodiments, the encapsulation layer 200 may be formed toentirely cover the organic electroluminescence unit 100 to preventexternal moisture and oxygen from infiltrating into the organicelectroluminescence unit 100.

In some embodiments, the encapsulation layer 200 may be formed of aglass material, thereby preventing the external moisture and oxygen frominfiltrating effectively. In some embodiments, the encapsulation layer200 may be formed of a low liquidus temperature material. In someembodiments, the encapsulation layer 200 may include at least one of tinfluorophosphates glass, chalcogenide glass, tellurite glass, borateglass, and phosphate glass. In some embodiments, the encapsulation layer200 may have an excellent moisture and oxygen blocking performance, andthus, lifespan of the organic light emitting display device 100 may beincreased.

In some embodiments, the encapsulation layer 200 may further includetungsten. In some embodiments, more stabilized and uniform glass may befabricated when tungsten is added. Thus, chemical durability of theencapsulation layer 200 may be improved.

In some embodiments, a melting point of the encapsulation layer 200 maybe 200° C. or less. In some embodiments, a melting point of theencapsulation layer 200 may be from about 150° C. to 200° C. In someembodiments, damage of each of the components of the organicelectroluminescence unit 100 due to the heat may be prevented, and theencapsulation layer 200 may be easily formed when heat is applied toform the encapsulation layer 200.

FIGS. 3 through 5 are perspective views showing encapsulation sheetsforming the encapsulation layer 200 of FIG. 1.

Referring to FIG. 3, an encapsulation sheet 200A may include a carrierfilm 210 and a first sheet 220 formed on a surface of the carrier film210.

In some embodiments, the carrier film 210 may be formed of one selectedfrom the group consisting of polyethylene terephthalate, polyester,polyacryl, polyepoxy, polyethylene, and polystyrene that have excellentthermal stability and mechanical stability, or may be formed of a glassmaterial.

In some embodiments, the first sheet 220 may be formed of a low liquidustemperature material, for example, at least one of tin fluorophosphatesglass, chalcogenide glass, tellurite glass, borate glass, and phosphateglass. For example, the tin fluorophosphates glass may include tin (Sn)by 20 to 80 weight %, phosphorus (P) by 2 to 20 weight %, oxygen (O) by3 to 20 weight %, and fluorine (F) by 10 to 36 weight %.

In some embodiments, the first sheet 220 may be formed by forming a filmof a low liquidus temperature material on the carrier film 210 by usinga deposition method, a vapor deposition method, a coating method, aspin-coating method, a sputtering method, a rolling method, or a laserablation method.

Although not shown in FIG. 3, an intermediate layer (not shown) may befurther formed between the carrier film 210 and the first sheet 220. Insome embodiments, the intermediate layer (not shown) may make theencapsulation layer 200 (refer to FIG. 1) separate easily from thecarrier film 210 when the encapsulation layer 200 is formed of the firstsheet 220.

In some embodiments, an encapsulation sheet 200B of FIG. 4 furtherincludes a second sheet 230 between the first sheet 220 and the carrierfilm 210. In some embodiments, the second sheet 230 may be a layerincluding tungsten, for example, the second sheet 230 may include H₂WO₃,or WO₃.

As described above, if the second sheet 230 is further formed, when heatis applied to the encapsulation sheet 200B to form the encapsulationlayer 200 (refer to FIG. 1), the low liquidus temperature material andthe tungsten react with each other to form stable and uniform glass. Insome embodiments, the reaction between the low liquidus temperaturematerial and the tungsten may be a diffusion reaction. Accordingly, thechemical durability of the encapsulation layer 200 (refer to FIG. 1) maybe further improved.

In some embodiments, a plurality of first sheets 220 and a plurality ofsecond sheets 230 may be stacked, and the plurality of first sheets 220and the plurality of second sheets 230 may be stacked alternately witheach other in order to improve the reactivity. In some embodiments, thetungsten included in the encapsulation layer 200 (refer to FIG. 1) maybe about 0.1 to 15 weight % due to the reaction with the low liquidustemperature material.

In some embodiments, an encapsulation sheet 200C shown in FIG. 5 mayfurther include a third sheet 235 between the first sheet 220 and thecarrier film 210. In some embodiments, the third sheet 235 may be formedof the same material as that of the second sheet 230 shown in FIG. 4. Insome embodiments, the third sheet 235 may be patterned on the carrierfilm 210. For example, the third sheet 235 may be formed on the carrierfilm 210 as stripe patterns; however, the present embodiment is notlimited thereto. In some embodiments, the third sheet 235 may be formedas dots or grating patterns.

In some embodiments, the low liquidus temperature material of the firstsheet 220 and the tungsten in the third sheet 235 may react with eachother to form stable and uniform glass when heating the encapsulationsheet 200C for forming the encapsulation layer 200 (refer to FIG. 1). Insome embodiments, the above reaction may be a diffusion reaction. Insome embodiments, the third sheet 235 may be patterned on the carrierfilm 210, and therefor the amount of tungsten included in theencapsulation layer 200 (refer to FIG. 1) may be easily adjusted.

FIGS. 6 through 8 are cross-sectional views illustrating a method ofmanufacturing the organic light emitting display device of FIG. 1.

Referring to FIGS. 6 through 8, the organic electroluminescence unit 100may be formed on the substrate 101 as shown in FIG. 6, and then, theencapsulation sheet 200A may be located on the organicelectroluminescence unit 100.

In some embodiments, the organic electroluminescence unit 100 may havethe structure shown in FIG. 2. In some embodiments, the organicelectroluminescence may have various structures that are well known inthe art.

In some embodiments, the encapsulation sheet 200A in which the carrierfilm 100 faces upward is located on the organic electroluminescence unit100.

In some embodiments, the, the encapsulation sheet 200A may be melted tocontact upper and side surfaces of the organic electroluminescence unit100 and a partial upper surface of the substrate 101 when theencapsulation sheet 200A is heated, as shown in FIG. 5.

In some embodiments, the first sheet 220 may be formed of the lowliquidus temperature material such as tin fluorophosphates glass,chalcogenide glass, tellurite glass, borate glass, and phosphate glass,and therefore the melting point of the first sheet 220 is 200° C. orless. In some embodiments, a melting point of the first sheet 220 may befrom about 150° C. to 200° C. Therefore, the first sheet 220 may bemelted to form the encapsulation layer 200 (refer to FIG. 8) withoutdamaging each of the components in the organic electroluminescence unit100 due to the heat.

Next, as shown in FIG. 8, after forming the encapsulation layer 200 bymelting the first sheet 220, the carrier film 210 may be separated to beremoved. In some embodiments, the carrier film 210 may be removed in aphysical manner.

FIGS. 6 through 8 show an embodiment where the encapsulation layer 200may be formed by using the encapsulation sheet 200A shown in FIG. 3. Insome embodiments, the encapsulation layer 200 may be formed by using theencapsulation sheet 200B of FIG. 4 or the encapsulation sheet 200C ofFIG. 5.

In some embodiments, where the encapsulation sheets 200B and 200C shownin FIGS. 4 and 5 respectively include the second sheet 230 and the thirdsheet 235, each including the tungsten, the encapsulation layer 200formed by using the encapsulation sheet 200B of FIG. 4 or theencapsulation sheet 200C of FIG. 5 may include more stabilized anduniform glass. Thus, the chemical durability of the encapsulation layer200 may be further improved.

In some embodiments, the encapsulation layer may be formed by using theglass material having excellent moisture and oxygen blocking property,and thus, lifespan of the organic light emitting display device may beincreased.

While the embodiments have been particularly shown and described withreference to exemplary embodiments thereof, it will be understood bythose of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present embodiments as defined by the following claims.

What is claimed is:
 1. An encapsulation sheet comprising: a carrierfilm; and a first sheet formed on the carrier film, wherein the firstsheet comprises at least one of tin fluorophosphates glass, chalcogenideglass, tellurite glass, borate glass, and phosphate glass.
 2. Theencapsulation sheet of claim 1, further comprising a second sheetbetween the carrier film and the first sheet, wherein the second sheetcomprises tungsten.
 3. The encapsulation sheet of claim 2, furthercomprising a plurality of additional first sheets and a plurality ofadditional second sheets, where each first sheet is stacked alternatelywith each second sheet.
 4. The encapsulation sheet of claim 2, furthercomprising a third sheet between the carrier film and the first sheet,wherein the third sheet is patterned as stripes, and the third sheetcomprises tungsten.
 5. The encapsulation sheet of claim 1, wherein thefirst sheet comprises tin fluorophosphates glass and the tinfluorophosphates glass comprises tin (Sn) by 20 to 80 weight %,phosphorus (P) by 2 to 20 weight %, oxygen (O) by 3 to 20 weight %, andfluorine (F) by 10 to 36 weight %.
 6. The encapsulation sheet of claim3, wherein at least one first sheet comprises tin fluorophosphates glassand the tin fluorophosphates glass comprises tin (Sn) by 20 to 80 weight%, phosphorus (P) by 2 to 20 weight %, oxygen (O) by 3 to 20 weight %,and fluorine (F) by 10 to 36 weight %.